6 ms·

Haskell Live: A Live Coding Adventure

131 points by nwjsmith 14y ago

veyron 14y ago
What is the editor / configuration used in the video ?
- nwjsmith 14y ago
  Looks like tmux + vim, using the Solarized Dark theme.
  - veyron 14y ago
    I gathered the vim part. Is he pressing a separate key to run the stuff in the lower-right window or is there a vim hook to do that automatically?
    - nwjsmith 14y ago
      For that I think he's using Guard (https://github.com/guard/guard/ https://github.com/guard/guard/)
      - ReinH 14y ago
        I'll make a video on my setup, but: Left: vim with Vim Haskell Mode[1], a pale imitation of emacs haskell minor mode that nevertheless gets the job done. ;) Top right: GHCi Bottom right: Guard, as mentioned, using guard-shell[2] to compile the file and run main using runghci. [1] https://github.com/lukerandall/haskellmode-vim https://github.com/lukerandall/haskellmode-vim [2] https://github.com/guard/guard-shell https://github.com/guard/guard-shell
        veyron 14y ago
        Maybe that info should be on the page itself somewhere. I wouldn't know to look at the github to find your guard script: https://github.com/haskelllive/haskelllive/blob/master/Guardfile https://github.com/haskelllive/haskelllive/blob/master/Guard...
        ReinH 14y ago
        Good call. I'll add that to the About. I'm going to do a quick supplemental vide on the setup as well between now and next episode.
clux 14y ago
Good workflow, nice simple start with chess types and the serialization/deserialization thereof. Enjoyable watch.
- ch0wn 14y ago
  I also really enjoyed the pacing and voice. I'm looking forward to the next episodes.
prezjordan 14y ago
This is awesome. Nice and approachable - well explained. I'd love if you also threw in some vim commands along the way.
- spacemanaki 14y ago
  I'd like to respectfully offer another opinion: I would NOT love if it some vim commands were thrown in. By all means, devote a single episode to tools, since the set up demonstrated might be complex to recreate, and it would likely be something a lot of people want to use too. But I don't think tips specific to a single editor have any place in screencasts that are about one programming language in general. An unobtrusive way to introduce editor tips that just came to mind would be to add subtitles with selected key-combos that might be nontrivial or not obvious. More than that would be a distraction, I think. Also, I don't know if YouTube supports multiple subtitle tracks... so that might be a big fu to deaf or hearing impaired programmers who want to follow along.
  - Avalaxy 14y ago
    Yes I wouldn't like it either because I don't use vim.
  - Oxryly 14y ago
    Seconded. Devote a short episode to tools, but don't mix the tools and programming too much.
  - prezjordan 14y ago
    Great suggestion, that's on par with what I had in mind. I was not implying OP should have a 3-minute segment on vim commands. Maybe just casually say "and I'm going to use :tab which allows me to select multiple lines and line up the equal signs" or something similar.
    - spacemanaki 14y ago
      > Maybe just casually say "and I'm going to use :tab which allows me to select multiple lines and line up the equal signs" or something similar. No, I wouldn't want them to casually say anything... that's why the subtitles would be an unobtrusive compromise, since you can just turn them off. I think this would be even more important if the screencast was targeted at new users of the language or framework or whatever, since the viewer might be confused and wonder if ":tab" was something to do with the syntax of the language.
runn1ng 14y ago
I have to say, I generally dislike video coding tutorials. First, it's difficult to google/copy-paste. Second, it just goes against the way I learn new programming languages - I generally read it, then try it, then experiment with it in some other ways, list few pages back/forth, experiment more, fail, then continue. Usually copypasting/rewriting chunks of code. "What happens when I do THAT? Oh, it fails miserably. Why? Oh, that's why." I can easily reread some parts. I can easily skim back/forth. While with the video, I don't want to hear the person more than twice, usually. The voice becomes annoying for the third time you hear it. I feel that videos work great for demonstrating a language. I can never actually learn any language from a video tutorial. (If you will bring the analogy of lecture - yes, this is partly true, but good lectures should be somehow interactive. The lecturer asks students, they can ask the lecturer back.)
- why-el 14y ago
  I actually enjoy these types of videos. I think actually typing stuff off of the video, and sometimes changing it a bit, works best for me. It's even better when you watch the video once, get the gist of it, then try to rewrite the whole thing. And it's plain faster. Having this tutorial in text will probably take you more time to read than you could have saved copy pasting.
- ballooney 14y ago
  > First, it's difficult to google/copy-paste That's a feature! No seriously. Among an august audience like HN people might have more discipline to properly grok the code they're copying, but I know of plenty of places where people will just copy and paste disparate chunks of tutorial code into their editor then start randomly changing lines and variables (with a hundred questions demanded of the poor folks in some irc channel) until it sort-of-but-not-quite works. Forcing people to write it from scratch, having had the construction demonstrated, seems to aid the mental digestion of the code much better. That's just my anecdotal experience anyway.
- codegeek 14y ago
  "I can never actually learn any language from a video tutorial." I like video tutorials/screencasts as long as they have the following : 1. Trainer starts with a basic list of topics/table of contents. Nothing fancy but give me an overall overview of what I will learn out of this. 2. A particular topic is taught gradually i.e. by starting with a simpler or even wrong way (as in best practices) and then improving it to show the more standard way. For don't just show me the final end product.Show me how to do it in a crude/simpler way, then improve the code (may be refactor etc) or add more features. Explain each improvement while you are doing it and WHY you are doing it.This makes us learn the gotchas and pitfalls and may be even best practices.For example, I can put all the code in one file to start with but then how can/should I refactor it in some recommended way? (MVC?) 2. Show me more than 1 way of doing something if it helps me learn the concept. Again, kind of related to #1. 3. Break the code on purpose and explain what the error message means. Then fix it and re-run. For example, in learning Django/Flask, if you are missing a template, it will crash/error out. So don't create the template right away. Build the code without template and let me see how it crashes. Then add the template and re-run to show me success. 4. Unless you are teaching design specifically, save the HTML/CSS/JS tricks/enhancements for the end. Show me the core product. I am sure there are more but these help me a lot personally. In fact, I am learning Python/Flask right now and looking to write my own tutorials on how I learnt it.
Oxryly 14y ago
Very cool. I don't have many Haskell coders where I spend my time, so it is nice to watch how someone with more experience tackles fairly basic programming tasks. The guard window and quickcheck in particular were eye-opening.
Toshio 14y ago
Awesome! This is exactly the kind of learning experience that would be useful to someone who has been studying Haskell intensely for a week.
ReinH 14y ago
Thank you all so much for your feedback. And thanks to the OP for posting this. I can't make everyone happy all the time but I'll do my best to make each episode better than the last. <3 HN
- tinco 14y ago
  Don't change too much, it's already a splendid format!
padrian2s 14y ago
Good job!!! I'm looking forward to the next episodes.
boothead 14y ago
For all those interested in emacs haskell mode this http://www.youtube.com/watch?v=E6xIjl06Lr4 http://www.youtube.com/watch?v=E6xIjl06Lr4 is about the best screencast I've seen covering the new stuff the Chris Done wrote. I'm using emacs prelude and it's a great environment right out of the box!
mattvanhorn 14y ago
This is really cool. I wish I had more free time, but I will be using what little I have for this (and learning vim as I go).
FuzzyDunlop 14y ago
Good screencast, there's a mistake regarding the piece colouring though. They're all black because all the characters are lowercase (and I think you meant to make the bottom row uppercase). It can be verified in the code, and in the REPL when it's being tested.
ek 14y ago
This is somewhat of a nitpick, but for one thing, writing code that is as obviously correct as possible is important in every language, not just in Haskell. Compositionality is one of the most valuable things we can exploit when programming. For another thing , the assertion that enumerating all the cases for a given function instead of using a lookup makes the code more obviously correct is somewhat flawed - it violates DRY, which is, like exploitation of compositionality, important in programming in general. Suppose the showPiece function had twice the number of cases. Would enumerating the cases individually or making the assertion that the code is more obviously correct as a result be reasonable? In my view, you are solving the same problem whether you use a lookup or enumerate the cases individually, and it's not even a very big problem - just put your tokens in the right order.
tsahyt 14y ago
This looks interesting. I somehow really like Haskell, although I never got around to dive into it. It's one of those languages that I want to learn one day but never have time to. So, watching those videos is kind of showing me how things are done the Haskell way, which is kind of strange for somebody like me who's entirely used to C89 ;)

131 points by nwjsmith 14y ago

veyron 14y ago

What is the editor / configuration used in the video ?

nwjsmith 14y ago
Looks like tmux + vim, using the Solarized Dark theme.
- veyron 14y ago
  I gathered the vim part. Is he pressing a separate key to run the stuff in the lower-right window or is there a vim hook to do that automatically?
  - nwjsmith 14y ago
    For that I think he's using Guard (https://github.com/guard/guard/ https://github.com/guard/guard/)
    - ReinH 14y ago
      I'll make a video on my setup, but: Left: vim with Vim Haskell Mode[1], a pale imitation of emacs haskell minor mode that nevertheless gets the job done. ;) Top right: GHCi Bottom right: Guard, as mentioned, using guard-shell[2] to compile the file and run main using runghci. [1] https://github.com/lukerandall/haskellmode-vim https://github.com/lukerandall/haskellmode-vim [2] https://github.com/guard/guard-shell https://github.com/guard/guard-shell
      - veyron 14y ago
        Maybe that info should be on the page itself somewhere. I wouldn't know to look at the github to find your guard script: https://github.com/haskelllive/haskelllive/blob/master/Guardfile https://github.com/haskelllive/haskelllive/blob/master/Guard...
        ReinH 14y ago
        Good call. I'll add that to the About. I'm going to do a quick supplemental vide on the setup as well between now and next episode.

clux 14y ago

Good workflow, nice simple start with chess types and the serialization/deserialization thereof. Enjoyable watch.

ch0wn 14y ago
I also really enjoyed the pacing and voice. I'm looking forward to the next episodes.

prezjordan 14y ago

This is awesome. Nice and approachable - well explained. I'd love if you also threw in some vim commands along the way.

spacemanaki 14y ago
I'd like to respectfully offer another opinion: I would NOT love if it some vim commands were thrown in. By all means, devote a single episode to tools, since the set up demonstrated might be complex to recreate, and it would likely be something a lot of people want to use too. But I don't think tips specific to a single editor have any place in screencasts that are about one programming language in general. An unobtrusive way to introduce editor tips that just came to mind would be to add subtitles with selected key-combos that might be nontrivial or not obvious. More than that would be a distraction, I think. Also, I don't know if YouTube supports multiple subtitle tracks... so that might be a big fu to deaf or hearing impaired programmers who want to follow along.
- Avalaxy 14y ago
  Yes I wouldn't like it either because I don't use vim.
- Oxryly 14y ago
  Seconded. Devote a short episode to tools, but don't mix the tools and programming too much.
- prezjordan 14y ago
  Great suggestion, that's on par with what I had in mind. I was not implying OP should have a 3-minute segment on vim commands. Maybe just casually say "and I'm going to use :tab which allows me to select multiple lines and line up the equal signs" or something similar.
  - spacemanaki 14y ago
    > Maybe just casually say "and I'm going to use :tab which allows me to select multiple lines and line up the equal signs" or something similar. No, I wouldn't want them to casually say anything... that's why the subtitles would be an unobtrusive compromise, since you can just turn them off. I think this would be even more important if the screencast was targeted at new users of the language or framework or whatever, since the viewer might be confused and wonder if ":tab" was something to do with the syntax of the language.

runn1ng 14y ago

I have to say, I generally dislike video coding tutorials. First, it's difficult to google/copy-paste. Second, it just goes against the way I learn new programming languages - I generally read it, then try it, then experiment with it in some other ways, list few pages back/forth, experiment more, fail, then continue. Usually copypasting/rewriting chunks of code. "What happens when I do THAT? Oh, it fails miserably. Why? Oh, that's why." I can easily reread some parts. I can easily skim back/forth. While with the video, I don't want to hear the person more than twice, usually. The voice becomes annoying for the third time you hear it. I feel that videos work great for demonstrating a language. I can never actually learn any language from a video tutorial. (If you will bring the analogy of lecture - yes, this is partly true, but good lectures should be somehow interactive. The lecturer asks students, they can ask the lecturer back.)

why-el 14y ago
I actually enjoy these types of videos. I think actually typing stuff off of the video, and sometimes changing it a bit, works best for me. It's even better when you watch the video once, get the gist of it, then try to rewrite the whole thing. And it's plain faster. Having this tutorial in text will probably take you more time to read than you could have saved copy pasting.
ballooney 14y ago
> First, it's difficult to google/copy-paste That's a feature! No seriously. Among an august audience like HN people might have more discipline to properly grok the code they're copying, but I know of plenty of places where people will just copy and paste disparate chunks of tutorial code into their editor then start randomly changing lines and variables (with a hundred questions demanded of the poor folks in some irc channel) until it sort-of-but-not-quite works. Forcing people to write it from scratch, having had the construction demonstrated, seems to aid the mental digestion of the code much better. That's just my anecdotal experience anyway.
codegeek 14y ago
"I can never actually learn any language from a video tutorial." I like video tutorials/screencasts as long as they have the following : 1. Trainer starts with a basic list of topics/table of contents. Nothing fancy but give me an overall overview of what I will learn out of this. 2. A particular topic is taught gradually i.e. by starting with a simpler or even wrong way (as in best practices) and then improving it to show the more standard way. For don't just show me the final end product.Show me how to do it in a crude/simpler way, then improve the code (may be refactor etc) or add more features. Explain each improvement while you are doing it and WHY you are doing it.This makes us learn the gotchas and pitfalls and may be even best practices.For example, I can put all the code in one file to start with but then how can/should I refactor it in some recommended way? (MVC?) 2. Show me more than 1 way of doing something if it helps me learn the concept. Again, kind of related to #1. 3. Break the code on purpose and explain what the error message means. Then fix it and re-run. For example, in learning Django/Flask, if you are missing a template, it will crash/error out. So don't create the template right away. Build the code without template and let me see how it crashes. Then add the template and re-run to show me success. 4. Unless you are teaching design specifically, save the HTML/CSS/JS tricks/enhancements for the end. Show me the core product. I am sure there are more but these help me a lot personally. In fact, I am learning Python/Flask right now and looking to write my own tutorials on how I learnt it.

Oxryly 14y ago

Very cool. I don't have many Haskell coders where I spend my time, so it is nice to watch how someone with more experience tackles fairly basic programming tasks. The guard window and quickcheck in particular were eye-opening.

Toshio 14y ago

Awesome! This is exactly the kind of learning experience that would be useful to someone who has been studying Haskell intensely for a week.

ReinH 14y ago

Thank you all so much for your feedback. And thanks to the OP for posting this. I can't make everyone happy all the time but I'll do my best to make each episode better than the last. <3 HN

tinco 14y ago
Don't change too much, it's already a splendid format!

padrian2s 14y ago

Good job!!! I'm looking forward to the next episodes.

boothead 14y ago

For all those interested in emacs haskell mode this http://www.youtube.com/watch?v=E6xIjl06Lr4 http://www.youtube.com/watch?v=E6xIjl06Lr4 is about the best screencast I've seen covering the new stuff the Chris Done wrote. I'm using emacs prelude and it's a great environment right out of the box!

mattvanhorn 14y ago

This is really cool. I wish I had more free time, but I will be using what little I have for this (and learning vim as I go).

FuzzyDunlop 14y ago

Good screencast, there's a mistake regarding the piece colouring though. They're all black because all the characters are lowercase (and I think you meant to make the bottom row uppercase). It can be verified in the code, and in the REPL when it's being tested.

ek 14y ago

This is somewhat of a nitpick, but for one thing, writing code that is as obviously correct as possible is important in every language, not just in Haskell. Compositionality is one of the most valuable things we can exploit when programming. For another thing , the assertion that enumerating all the cases for a given function instead of using a lookup makes the code more obviously correct is somewhat flawed - it violates DRY, which is, like exploitation of compositionality, important in programming in general. Suppose the showPiece function had twice the number of cases. Would enumerating the cases individually or making the assertion that the code is more obviously correct as a result be reasonable? In my view, you are solving the same problem whether you use a lookup or enumerate the cases individually, and it's not even a very big problem - just put your tokens in the right order.

tsahyt 14y ago

This looks interesting. I somehow really like Haskell, although I never got around to dive into it. It's one of those languages that I want to learn one day but never have time to. So, watching those videos is kind of showing me how things are done the Haskell way, which is kind of strange for somebody like me who's entirely used to C89 ;)